Welding fittings onto pipe is a difficult undertaking, often requiring a pair of men to perform satisfactorily. It is not unusual for one man to orient, align and support fittings, such as tees, ells and flanges, against the pipe ends while the other man welds them together. This is hazardous work where burns, bruises, strains and broken bones are not uncommon. Of course, the work is costly because the men performing it must be highly skilled and well-paid.
Additionally, both of these men must be covered by expensive insurance to offer them some protection in the event of an accident.